Stacked magnetic inductor and method
An electronic device and associated methods are disclosed. In one example, the electronic device includes a package with integrated inductors. In selected examples, the package includes a core layer having a core thickness and through holes. The package further includes inductor structures within the through holes, such that an inductor structure has a length exceeding the core thickness.
1 . A package structure with integrated inductors, comprising:
a core layer having a core thickness;
a plurality of laminate substrate layers on the core layer, the plurality of laminate substrate layers having a higher coefficient of thermal expansion (CTE) than a CTE of the core layer, and a plurality of via layers within the laminate substrate layers, the plurality of via layers having not fewer than three via layers;
a plated through hole extending through the core layer and coupled to a lower-most one of the plurality of via layers adjacent the core layer; and
an inductor comprising a magnetic material surrounding a conductive material, the magnetic material and the conductive material each having a length exceeding the core thickness, the inductor extending through the core layer and a portion of the plurality of laminate substrate layers beyond the lower-most one of the plurality of via layers to couple to an upper-most one of the plurality of via layers distal the core layer such that the length of each of the magnetic material and the conductive material extends beyond the lower-most one of the plurality of via layers and at least one via layer between the lower-most one of the plurality of via layers and the upper-most one of the plurality of via layers.
2 . The package structure of claim 1 , wherein the core layer comprises woven glass fabric embedded in an epoxy resin.
3 . The package structure of claim 1 , wherein the core layer comprises a ceramic material.
4 . The package structure of claim 1 , further comprising:
a plurality of second laminate substrate layers on the core layer and opposite the core layer from the plurality of laminate substrate layers, and a plurality of second via layers within the second laminate substrate layers, the plurality of second via layers having not fewer than three via layers.
5 . The package structure of claim 4 , wherein the inductor extends beyond a lower-most one of the plurality of second via layers to couple to an upper-most one of the plurality of second via layers such that the length of each of the magnetic material and the conductive material extends beyond the lower-most one of the plurality of second via layers and at least one second via layer between the lower-most one of the plurality of second via layers and the upper-most one of the plurality of second via layers.
6 . The package structure of claim 5 , wherein the plated through hole is coupled to the lower-most one of the plurality of second via layers.
7 . The package structure of claim 1 , wherein the inductor comprises a coaxial magnetic inductor.
8 . The package structure of claim 1 , wherein the conductive material is a cylinder.
9 . The package structure of claim 1 , wherein the magnetic material comprises magnetic paste.
10 . The package structure of claim 9 , wherein the magnetic paste comprises a polymer resin impregnated with particles of the magnetic material, the magnetic material comprising at least one of iron, nickel, and cobalt.
11 . The package structure of claim 1 , further comprising:
a die coupled to the plurality of via layers.
12 . The package structure of claim 11 , further comprising:
a bridge within the laminate substrate layers.
13 . A package structure with integrated inductors, comprising:
a core layer having a core thickness, the core layer comprising a ceramic material;
laminate substrate layers on the core layer, the laminate substrate layers having a higher coefficient of thermal expansion (CTE) than a CTE of the core layer, and not fewer than three via layers within the laminate substrate layers, the via layers comprising a lower-most via layer adjacent the core layer, an upper-most via layer distal the core layer, and one or more middle via layers between the lower-most via layer and the upper-most via layer;
a plated through hole extending through the core layer and coupled to a bottom of the lower-most via layer; and
an inductor comprising a magnetic material surrounding a conductive material, the magnetic material and the conductive material each having a length exceeding the core thickness, the inductor extending through the core layer and beyond the lower-most via layer and the one or more middle via layers to couple to a bottom of the upper-most via layer such that the length of each of the magnetic material and the conductive material extends beyond the lower-most via layer and the one or more middle via layers.
14 . The package structure of claim 13 , further comprising:
second laminate substrate layers on the core layer and opposite the core layer from the laminate substrate layers, and a plurality of second via layers within the second laminate substrate layers.
15 . The package structure of claim 14 , wherein the second via layers comprise a lower-most second via layer adjacent the core layer, an upper-most second via layer distal the core layer, and one or more middle second via layers between the lower-most second via layer and the upper-most second via layer.
16 . The package structure of claim 15 , wherein the inductor extends beyond the lower-most second via layer and the one or more middle second via layers to couple to the upper-most second via layer.
17 . The package structure of claim 16 , wherein the plated through hole is coupled to the lower-most second via layer.
18 . The package structure of claim 13 , wherein the inductor comprises a coaxial magnetic inductor.
19 . The package structure of claim 13 , wherein the conductive material is a cylinder.
20 . The package structure of claim 13 , wherein the magnetic material comprises magnetic paste.
21 . The package structure of claim 20 , wherein the magnetic paste comprises a polymer resin impregnated with particles of the magnetic material, the magnetic material comprising at least one of iron, nickel, and cobalt.
22 . The package structure of claim 13 , further comprising:
a die coupled to the via layers.
23 . The package structure of claim 22 , further comprising:
a bridge within the laminate substrate layers.